Consider default zoom scale for mobile viewport.
Consider default zoom scale for mobile viewport.

issue: 4482888
Change-Id: I6a100700b7a7e9464b397f219217225f3ada0f63

xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base,xorware/android_frameworks_base